Foldable electric wheelchair

ABSTRACT

A foldable electric wheelchair that includes an array of support frame members strategically joined together at hinge joint points to allow the support user seat, a back support frame, a main support frame and a lower support frame to be easily manually folded into an array that are substantially parallel in the same plane occupying a small volume. The electric motors are powered by a pair of batteries each of which is mounted inside hollow main frame support members out of the way to reduce the overall volume and weight of the electric wheelchair

CROSS REFERENCE TO RELATED APPLICATIONS

N/A/

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

N/A

BACKGROUND OF THE INVENTION

Field of the Invention

This invention relates generally to a foldable electric wheelchair, andspecifically to a foldable electric wheelchair that is lightweight,easily collapsible, portable, safe and comfortable.

Description of Related Art

The use of electric wheelchairs to confer mobility and transport topeople with a disability is well known in the prior art. While it isvery desirable to have a powered electrical wheelchair, the use ofelectric motors and batteries adds considerable weight and bulk to theoverall weight and size. Conventional electric wheelchairs tend to beheavyweight and large in size which works against portability and itsfoldablity. Often it is desirable to store the wheelchair when not inuse and especially to transport the device in a vehicle so that thewheel chair can travel with the person with the disability and beavailable wherever that person is located.

The invention described herein overcomes the problems of heavy weightand large volume or bulk for an electric wheelchair by providing awheelchair that is light weight and foldable and easy to carry while atthe same time remains safe and comfortable for the user.

In order to accomplish the improved functionality of the invention, thewheelchair is foldable using a plurality of connecting frame membershaving hinge joints postioned as connectors for the frame members thatcan fold sections in a parallel position to decrease the size of thewheelchair. Also the folding design described herein in the inventiondecreases the overall weight of the wheelchair by a special location ofthe battery into the frame itself. By strategic positioning of thestructural support members of the invention and the hinge jointsconnecting frame members together, the entire unit can be easily foldedand collapsed into a very small size for increased portability and easeof storage.

SUMMARY OF THE INVENTION

A foldable electric wheelchair comprising a foldable support frame, fourwheels attached to the support frame, a pair of motors attached near therear wheels for the driving unit, a support seat for the user connectedto the foldable support frame and including a pair of tracks forslidably connecting the user seat to the foldable support frame and apower source such as a pair of batteries that are mounted inside twohollow main support frame members

The wheelchair foldable support frame includes two substantiallyparallel main frame support members that can be rectangular incross-section and that are hollow, a back support frame that is L-shapedon each side (left and right side) and pivotally connected to one sideof both of the two main frame members, a lower support member comprisinga pair of parallel rods having one end connected to the lower end of theback support member integrally, a front vertical support member made upof two parallel rods on each side that are pivotably connected to themain frame member and the lower frame members. The hinge points thatallow pivoting of the support rods and main frame members arestrategically positioned so that when the entire unit is collapsed, themain frame members are in a parallel relationship with the support seatand back support frame resulting in a small volume when folded.

A rigid support seat having a pair of parallel track members one on eachside is slideably connected to the back support frame members on eachside and the main frame support members at the front of the device. Theback support frame members and rods are connected into the paralleltracks in the support seat that allows the back support member to moveforward relative to the seat in the collapsing mode so that the seatends up substantially parallel to the main support frame members and theback support member. The front vertical support frame has parallel rodson each side of the device that are pivotably attached to the lowersupport frame and the main support frame members also includes anattachment portion to receive the front wheels of the device. The lowersupport frame member may also include a foot rest that can be attachedto receive the feet of the user.

The two main horizontal support frame members are strong rigid buthollow to provide much of the heavy lifting of the device. However eachmain support frame member provides sufficient storage volume in itshollow inside to receive a battery in each frame member that can be usedto power each motor

The wheelchair has two arm rests that are attached to the back supportframe on each side that pivot out of the way when the entire unit iscollapsed.

A pair of protector plates mounted on each side of the wheelchairadjacent the user seat and attached to the main support frame on eachside that when positioned above the seat keep the occupant in the seatfrom falling out of the wheelchair. These protector plates can rotatefor a storage position.

By providing a specific array of frame members with strategicallylocated pivotal joints, the invention achieves a very light weight,compact collapsible and foldable electric wheelchair that is safe andsupports a large amount of weight but can be collapsed a very small unitand easily stored in a vehicle.

It is an object of this invention to provide a lightweight electronicwheelchair that is easy to fold and carry and safe and comfortable forthe user. It is another object of this invention to provide a foldableelectronic wheelchair that is relatively small in volume for storagewhen folded while also when in use it is safe and comfortable for theuser. These and other objects of the invention will become clear to oneof skill in the art.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevational view of a foldable electric wheelchairrepresenting the invention in an operational mode.

FIG. 2 is a side elevational view of a foldable electric wheelchairrepresenting the invention in a folded collapsed storage mode.

FIG. 3 is a side elevational view of a schematic diagram representingthe frame members and their folding points

FIG. 4 is a side elevational view of the back support frame member usedin the invention.

FIG. 5 is a perspective view of the main support frame that houses thebattery as is used in the invention.

FIG. 6 is a side elevational view of the main support frame member andthe battery extended there from

FIG. 7 is a cutaway perspective view of the wheels and motors used inthe present invention

FIG. 8 is a perspective view of a handle used in the present invention.

FIG. 9 is a perspective cutaway view of the wheelchair arm rest and aportion of the top guide handle.

DETAILED DESCRIPTION

Referring now to FIG. 1 a foldable electric wheelchair 10 representativeof the invention is shown. The wheelchair frame has a main supportmember 12 that is rectangular in cross-section and is hollow inside butis made of a very rigid metal for strength. The main support member 12is connected at its lower end to a motor and wheel 22. Mounted inside ofthe main support member 12 is a battery 40 which is discussed below. Bystoring the battery inside the main support frame member 12, a separatebattery platform is eliminated greatly reducing the volume of thewheelchair especially when folded. This also reduces the overall weightof the wheelchair. The upper end of the main frame support member 12 ispivotally connected to the rigid seat 20 having a track 20 a and also toa front vertical frame rod 18 pivotally.

The wheelchair supporting frame also includes a back support framehaving back support frame member 14 that is L-shaped slidably attachedto the rigid seat 20 and the track 20 a which allows relative movementbetween the seat 20 and the back support frame member 14 when thewheelchair is collapsed and folded. The L-shaped back support framemember 14 is connected to a lower frame rod 16 at one end pivotally. Thelower support frame rod 16 has a curved end portion that connects to afoot rest 26 that is foldable. The front vertical support rod 18 isconnected to the front wheel 24 which is explained below. There is avertical front support rod 16 on each side of the wheelchair.

An elliptical shape protector panel 32 is pivotally connected to themain frame support member 12 on each side of the wheelchair 10 that actslike a guard for the user when the user is seated in the wheelchair. Theguard 32 protects the user from accidentally sliding sideways during useof the device. The protector panels 32 can be firmly held in place orrotated through the use of the rotatable joint 42.

The wheelchair 10 also includes a pair of armrests 28 that can pivotabout a pivot joint 36. Attached at one end of armrest 28 is a powercontrol box 30 with a joy stick control member that allows the user tocontrol power to the electric motors for driving the unit.

Attached to the top end of the back support frame member 14 is amanually utilized U-shaped handle bar 34 going across the top back fromside to side that can be used to manually direct the wheelchair. Thehandle bar 34 is pivotally attached to the upper back support framemember 14 with a hinge joint 36. Attached on each side at the bottom ofthe wheelchair 10 or pair of wheels 38 to prevent the wheelchair fromrotating backwards.

Referring now to FIG. 2 the foldable electric wheelchair is shown in itsfolded or collapsed position. When folded, the main support frame 12 issubstantially parallel to the user seat 20, the back support frame 14and the lower support frame rod 16. Because of the strategic length andpositioning of each of the independent frame member support systems andthe rotatable joints, the wheelchair can be collapsed and folded into avery small volume as shown in FIG. 2.

The foldable electric wheelchair 10 is shown in the operating positionin FIG. 1. Because of the size and disposition of each of the framesupport members including the main frame support member 14 and thelocation of the pivot joints for the L-shaped back support member 14,the rigid seat 20 having tracks 20 a, the lower support frame rod 16pivotally attached to the back support member 14 and the front supportframe rod 18 being pivotally attached to both the mainframe member 12and frame support rod 16, the wheelchair is capable of being folded intoan extremely small volume as illustrated in FIG. 2.

Referring now to FIG. 3, a schematic diagram is shown of the supportframe members and rods that provide the strength and the ability to foldthe electric wheelchair into a very small volume and compact unit forstorage. The main support frame member 12 is an elongated hollowrectangular tube made of a rigid metal to provide the primary supportfor the entire wheelchair on each side. The lower end of frame member 12is connected to the back wheel 22 which is also connected to a motor(not shown in FIG. 3). Inside the frame member 12 is a removable battery40. The top end of frame member 12 is connected to the rigid seat 20 byhinge joint “C”. The bottom top edge of frame member 12 is connected toan L-shaped back support frame member 14 at hinge joint “A”. The lowerportion of the L-shaped back support member 14 is connected to a lowersupport rod 16 at hinge joint “F”. The rigid seat 20 that the user sitson includes a track 20 a that is slidably connected to the back supportmember 14 at hinge joint “B”. A front support rod 18 which has a curvedportion is connected to the lower support frame rod 16 at the hingejoint “E” along its lower edge into the main support frame member 12 atits upper end at hinge joint “D”. The front vertical support rod 18 alsois connected to the front wheel 24. By having strategically sized rigidframe members and strategically positioned hinge joints to permitrotation and sliding action, the wheelchair can be folded into a verysmall volume in accordance with the invention.

Folding the wheelchair frame assembly for the wheelchair allows the backsupport frame member 14 which is L-shaped to be pushed toward mainsupport frame member 12 causing the lower end of the back support memberto rotate downwardly. Lower support frame rod 16 moves upwardly whilethe front vertical support frame rod 18 moves inwardly towards the mainsupport frame member 12. When the back support frame member 14 is pushedforward, rigid chair 20 based on track 20 a connected at joint “B” movesdownwardly pivoting around joint “C” moving into a parallel relationshipwith the main frame support member 12. The result is a configurationthat shows the folding wheelchair above in FIG. 2.

FIG. 4 shows the back support frame member 14 that is L-shaped thatconnects to the seat 20 and the lower frame rod 16. The back supportframe member 14 has a parallel part one on each side of the wheelchairthat are connected together by rigid tubes forming a rigid unit left andright side members in parallel.

FIG. 5 shows the main support member 12. This is connected at its bottomto a back wheel 22. On each side of the wheelchair there is a mainsupport frame member 12 in parallel. The inside of the frame member 12is hollow and rectangular in cross-section and includes a battery ineach side for running the motor that is connected to the back wheel onits own particular side. Thus there are two batteries 40 each mounted ineach frame support member 12 that include wiring (not shown) to connectto the power control unit for driving a respective motor mounted on theleft wheel 22 and the opposing wheels. The wheelchair includes twoseparate motors one in each back wheel that connect to batteries mountedin the main support frame member 12. The mainframe support member 12also includes a plurality of pivotal joints for the fold up operationincluding pivotal joints A, C, and D as shown.

Referring now to FIG. 6, the main support frame member 12 is shownconnected to wheel 22 and a support wheel 38 attached thereto. Therectangular battery 40 is shown partially exposed that fits into thehollow inside of the main support frame member 12. A battery cap endmember 40 a is connected to one end of battery 40 that acts as an endcap against the main support frame member 12. By placing the battery 40on each side of the wheelchair within each main support frame member 12,the battery is hidden from view and does not take up extra spaceespecially when the wheelchair is folded. An electrical control unit andwiring and the electric motors are not shown in FIG. 6 that are attachedelectrically to each battery 40.

Referring now to FIG. 7, electric motors 44 for the left and right rearwheels 22 are shown that are used to propel the electric wheelchair. Themotors 44 are attached by wires not show to a control unit attached tobatteries 40 that are stored in the main support frame member 12.

FIG. 8 shows the top horizontal manually engageable handle bar formanually controlling the wheelchair by hand that can be used by anassistant to the user of the wheelchair. The top bar 34 can be rotatedfor storage using hinge joint 36 when not in use.

FIG. 9 shows a portion of the top handle bar 34 and hinge joint 36connected to back support frame 14 and an armrest 28 on one side of thewheelchair. The armrest 28 can also rotate to a storage position with ahinge joint 28 a for storage. The armrest locks in place perpendicularto the back support frame 14 when in use.

The electric wheelchair disclosed herein can be folded into a very smallvolume for portability and storage space limitations. This makes theentire wheelchair a very portable unit for the user so that it can bestored in a vehicle or other areas when not in use and for transport ofthe user. By locating the batteries within two main storage supportframe members the batteries are out of the way and do not require aseparate battery storage platform which would take up extra volume andweight.

The invention has been described herein but may have additionalembodiments that would be obvious to one of ordinary skill in the art.

What is claimed is:
 1. A foldable electric wheelchair having a usersupport seat and a seat frame, a pair of front wheels, a pair of reardrive wheels, a pair of electric motors, one attached to each rear wheelfor driving the wheelchair, and a foldable support frame having aplurality of pivotal joints among the frame members, the foldablesupport frame comprising: a pair of main support frame members, saidmain support frame members each being hollow and made of a rigidmaterial, said support frame member each having a lower end and an upperend, said support frame member lower end being attached to a rear wheeland a motor, a back support frame that includes a pair of frame membersvertically mounted on each side and pivotably attached at its base tosaid main support frame member on each side, each back support framemember on each side attached to said user seat, said user seat having apair of parallel side tracks and said back support frame member attachedmovably to said user seat side tracks to allow relative movement betweensaid back support frame and said user seat; said back support framemember being L-shaped including on each side of said wheelchair; a lowersupport frame having support frame members on each side of saidwheelchair, the lower support frame members each having a distal end anda proximal end, said distal end of said lower support frame memberspivotally attached to one end of said back support frame for pivotalmovement; a front vertical support frame member on each side of saidwheelchair, said front vertical support frame member having an upper endand a lower end, said upper end of each vertical support frame memberbeing pivotally attached to said main support frame at the upper end ofsaid main support frame on each side, said lower end of said frontvertical support member pivotably attached on each side to said lowersupport frame members; said front vertical support frame members lowerend being attached to a pair of front wheels, one in each side forsupporting said wheelchair; and said main frame support memberspivotally attached to said back support members, said lower supportmembers and said front vertical support members all pivotally attachedand positionable in an unfolded position for use as a wheelchair and ina folded position wherein the back support frame members aresubstantially parallel to said mainframe support members in a storageposition.
 2. An electric wheelchair as in claim 1, including: batterymounted inside each of said main support frame members and removable andinsertable into said mainframe support member on each side of saidwheelchair